The invention relates generally to power supplies formed of multiple voltage sources, and more particularly to switching systems for selectively configuring the multiple voltage sources in series, parallel, or series-parallel configurations. The invention applies particularly to solar panels.
Solar panels are used to convert solar energy to electrical energy. A solar power system is generally made up of a number of solar panels whose outputs are combined. However, because of changing solar conditions and different loads, the output of the solar power system and the load requirements are not constant. For example, at different times of the day (early morning or midday) and year (summer or winter), and under changing weather conditions (sunny or cloudy), the output voltage from each solar panel will vary significantly. Likewise, operation of a solar powered water pump under different conditions, or other applications such as powering lighting systems or charging batteries, will require different power levels, i.e. different output voltages and/or different output currents, from the solar power system.
Unfortunately, no system presently exists which allows rapid reconfiguration of a multi-panel solar power system to meet changing power production conditions and to respond to changing power demand requirements. Multi-panel systems are generally hard wired into a particular configuration which cannot readily be altered to effectively use the available outputs of each panel to satisfy user demands. Present solar systems do not offer a simple control apparatus for either electronic or manual switching from series to parallel arrangements.
The problems of multi-panel solar systems also apply to other power systems made up of multiple voltage sources where the individual voltage source outputs vary and/or the user demands change significantly during operation of the power system.
Accordingly it is desirable to provide multi-panel solar power systems or other multi-source power systems with simple control or switching systems which allow the multiple solar panels or other voltage sources to be readily reconfigured or switched into various series, parallel, or series-parallel configurations.
Accordingly it is an object of the invention to provide a power system formed of multiple solar panels or other voltage sources in which the multiple panels or other voltage sources are readily switchable into various series, parallel, or series-parallel configurations.
It is another object of the invention to provide a multi-panel solar power system which can be rapidly and easily reconfigured to meet changing power production conditions and to respond to changing power demand requirements.
It is also an object of the invention to provide a solar system with a simple control apparatus for either electronic or manual switching from series to parallel arrangements.
The invention is a readily switchable multiple solar panel (or other voltage source) system in which the individual solar panels are interconnected with a control or switching apparatus which allows the solar panels to be readily switched into various series, parallel, or series-parallel configurations. In a preferred embodiment, a relay is connected to each solar panel so that in a first state, the panels are in series where the total voltage is the sum of each individual panel""s voltage. When the relay is switched to the second state, each solar panel is in parallel, where the total voltage is a single panel""s voltage and the current is multiplied by the number of panels. With each relay connected in a parallel arrangement, a simple control switch in series with the relay coils can control the panel switching. The coil of each relay can also be individually controlled. Thus the switchable multiple voltage source power supply of the invention is formed by connecting individual panels (or other individual voltage sources) through a switching system which provides selective configuration of the individual panels into series, parallel, or series-parallel arrangements.